Centrifugal casting apparatus



J. T. PRATT Se t, 38, 1923.

TILE AND FASTENING MEANS THEREFOR Filed June' 6. 1922 and aten -ar. ll, l9.

i or perm,

3* MGM GABTING v Application filed February 27, 1922. Serial no. $39,415.

To all whom it may concern:

Be it known that I, JOHN A. RATHBONE, a citizen of the United States of America, residin at Detroit, in the county of Wayne gtate of Michigan, have invented certain new and useful Improvements in Centrifu al Casting Apparatus, of which the following is a specification, reference being had therein to the accompanying drawings.

The invention relates to apparatus for centrifugally formin castings and consists in various features construction as hereinafter set forth.

In the drawings:

Figure 1 is a sectional elevation of the machine;

Figure 2 is a plan view thereof;

Figure 3 is a vertical longitudinal section in the plane of the axis of the rotary spindle.

In the present state of the art annular castings have been formed by the pouring centri of'the mold, so that when the apparatus is with an axial passa of the molten metal into a revolving mold .in which it is distributed by centrifugal action. In order that the castings may be quickly formed and removed, it is desirable to maintain the surface of the mold at a relatively low temperature. This I have accom lishedin my improved apparatus-by a flui cooling system in which the cooling medium is held in contact with the metal walls to be cooled by centrifugal action and in which steam or. vapor generated is qluickliy1 removed. I also make use of the gal action for locking the sections stopped, these sections may be easily separated for the removal of the work.

In detail, A is a sutiable base which, as shown, is in the form of the tank. B is a standard rising from this base and preferably cast integral therewith, carrying a its upper end a bearing C for a revolving inclined shaft D. There is also a bearing E for the lower end of the shaft and between the bearings C and E there is connected to the shaft a drivin mechanism shown as a bevel gear wheel on the shaft meshing with a driving bevel gear wheel Gr.

At the upper end of the shaft D is mounted the mold H, preferably by providing the integral flange 1 upon the shaft, which is bolted or otherwise secured tothe body of the mold. The walls and also the base of the mold are hollow and in communication throu h the shaft D. At the lower end 0 the sha t there is provided a suitable water supply connection J having a stufiing box K or other means for a connecting it to the revolving part. The water from this connection passes upward into the hollow walls of the mold body and to permit the escape of hot water and steam there is also provided an exit throu h the axis ofthe shaft. Preferabl this is ormed by an inner tube L, which is held in position by a spider M or other suitable means, and at its lower end is in communication with a cross channel N passing out through the wallsof the shaft. llhus when water is introduced under pressure, it will flow upward adjacent to the walls of the tube and nto the chamber in the mold body, where t is thrown outward by centrifugal action, wlule the heated water and steam being of less' density, will be forced inward through the axial passage and will eventually escape through the channel N.

For retaining the metal in the mold durmg the pouring operation there is provided a removable cover plate This is of annular form and at one side is hinged to the body, as indicated at P, while at its opposite side it is provided with a' hooked arm Q engaging a latch or detent R. This latch being pivoted to the body of the mold will be pressed outward by centrifugal action, so

that the more rapidly the mold is revolved the firmer the en agement between the latch and the arm. he engagin faces of the latch and the arm are bevelled so that the centrifu pure will also draw the cover plate titly against the body of the mold. A light spring S may be provided to initially press the. latch outward, but this is not depended upon for locking the parts as the centrifugal pressure will accomplish such result.

With the ap aratus as described, in use, the mold being eld in inclined position, permits of conveniently pouring the metal thereinto from a ladle or other source of supply. Before pouring, rotary motion is impa to the shaft and mold and the metal, upon contacting with the walls of the mold, will be set into motion and uniform]. distributed. Any excess of metal will ow over the inner margin of the cover plate 0, thereby exactly gaugin the amount retained for each casting. i reason of the cooling of the mold body, the molten metal is quickly chilled and solidified, so that in a very short time the machine can be stopped and the ill) forcin casting'removed. In removing the casting the cover plate is first turns outward on its hinge, after which the casting can be withdrawn, the shrinkage bein suflicient to separate it from the mold If desired, the castings may subsequent y be subjected to an annealiniprocess to change the characterof the met To catch the molten metal which would be thrown off centrifugally in case of the over filling of the mold I have arranged an annular shield or guard T which com letely surrounds the mold without inter erin with access thereto. This guard has a note U cut in the lower portion of the flange thereof adapted to engage the cover plate 0 when open and there y to lock the s indle from rotation. This forms a safety evice, which insures that the cover plate will be closed before motion is imparted to the machine.

The machine is preferably driven by an electric motor mounted on the base, as indicated at V, and for convenience in controlling this motor the controlliigg switch W is mounted on the pedestal within easy reach of the o erator. There is also preferably provid a brake for quickly stopping the rotation, this consisting of a lever Y having a brake shoe Y for engaging the motor shaft and a pedestal Y for applying braking power thereto.

What I claim as my invention is:

1. An apparatus for centrifugally forming castin comprising a revoluble annular mold aving hollow walls, a hollow shaft on which said mold is mounted, and means for introducing a cooling fluid into said hollow mold through said hollow shaft and for forcin the heated fluid and vapor axially outwa through said shaft by centrii action.

2. i t apparatus for centrifugally forming w s, comprising a revo uble annular mold aving hollow walls, a hollow shaft on which said mold is mounted, means for forcing a cooling fluid into said hollow walls through said hollow shaft, and a vent for the escape of heated fluid and vapor ccunicating with the axis of said hollow shaft, whereby circulation is forced by centrifugal action.

3. An apparatus for centrifugall 'forming castings, comprising an incllne hollow rotary shaft, an annular mold having h0llow walls mounted on said shaft, means for a cooling li uid into said hollow walls t rough said ho low shaft, a vent tube arrange. axially within saidhollow shaft, communicating at its lower end with a transversely extending escape port, whereby the heated fluid and vapor will be forced outward oentrifugally through said vent tube and escape port.

a. An apparatus for centrifugally forming castings, comprising an inclm LMIWM ing castings, comprising a rotary mold, a cover plate there or, a latch for holding said cover plate forced outward by centrifu- 1 action, and coacting cam surfaces on said latch and cover late by which the con-- trifugal pressure w' press the cover against the 1". l of the mold.

ti. apparatus for centrifugallg in casting, comprising an incline ho ow shaft, an annular mold mounted on said shaft and having hollow walls in communication with the same, means for introformducing a cooling fluid through said hollow shaft and into the hollow walls of. said mold, and an annular cover plate for said mold through the 0 en center of which the molten metal may poured into contact with the chilled walls of the mold.

6. An apparatus for eentrifugall formrotary shaft a mold mounted on said shaft, an annular cover plate for said mold permit.- ting the pouring of the molten metal therein and retaining the metal re uired for the casting while permitting ove ow of an ex.- cess of metal, and an annular shield surroundin said mold for catching the excess metal w on thrown out centrifugally from the mold.

7 An apparatus for centrifugallg forming castings, comprisin andncline rotary shaft, a mold mounte on said shaft, a hinged annular cover plate for said mold permitting the pouring of the molten metal thereinto and retaining the metal for the casting while permitting overflow of excess metal, a latch for holding said cover plate locked when the mold is revolvin, an annular shield surrounding said moloi for catching the overflow of molten metal thrown out centrifugally, and means for fog an interlocking engagement between said cover plate and mold when the former is open to prevent the imparting of rotary motion to the mold.

a. An apparatus for centrifugally forming castings, comprising a revoluble annular mold having hollow walls, a hollow shaft on which said mold is mounted, means for introducing a cooling fluid into said hollow mold through said hollow shaft and for forcing the heated fluid axially outward throu h said shaft. 7

9. n apparatus for centrifu ally forming castings, comprising a revolu le annular mold having hollow walls, a hollow shaft on which said mold is mounted, means for introducing a cooling fluid into said hollow mold through said hollow shaft, and a tube within said hollow shaft for withdrawing the heated fluid, said tube communicating with said mold substantially at the axis thereof.

10. An apparatus for centrifugally forming casts, comprising a rotary mold, a

rotary its ' to said mold by centrifuga action when the cover plate therefor, surface, and a latch cam surface in e mentioned cam sur ace whereby the cover is pressed against said mold through centrifugal action.

11. An apparatus for centrifugally forming castings, comprisinga rotary mold,'a cover plate therefor, a spring p latch for removably holding said cover plate to said mold when the latter is stationary, and coacting cam surfaces for ressing the cover provided with a cam aving a cooperating mold is rotating.-

agement with said first 12. An apparatus for centrifugally form- 16 ing castin com rim'ng' a rotary mold, a cover plate there or, provided with a cam surface, a latch pivotally secured to said mold, a cooperating cam surface on said latch engageable with the cam surface on an said cover whereby the latter is pressed to said -mold through centrifugal action of mid latch, and a vspring for removably engaging the latch with said coverwhen the apfaratus is stationary.

n testimony whereof I afix my signatum. 

